The present invention generally relates to surgical cutting instruments and more particularly to a laparoscopic instrument having a hook-shaped blade structure.
A wide variety of bladed instruments have been developed for use in surgical procedures. Many specialized shapes have been used for the blades of such instruments to allow the surgeon to easily make different types of incisions and cuts in tissue. In the past, instruments with curved blades have been utilized in operations to make certain specialized cuts easily and with reduced trauma to surrounding tissue.
One surgical instrument employing a curved blade is shown and described in U.S. Pat. No. 3,610,246 to Salmon. This patent discloses a knife blade having a curved cutting edge and including two protuberances along either side of the rear of the blade. The protuberances are employed so that the two cut edges of a membrane or blood vessel ride along the top of the protuberances to cause the walls of the membrane or vessel to be spread apart as the surgeon makes the cut.
Certain disadvantages are associated with typical curved blade instruments such as the tendency for such blades to stray from the intended cutting path and thereby damage surrounding tissue.
Accordingly, it has been one object of the present invention to provide a hook-shaped knife having a specialized tip design for allowing dissection in a select tissue plane without injuring deeper tissue structure.
It has been another object of the invention to provide a knife having an electrical coagulation outlet electrically connected to the blade for enabling hemostasis and further having an electrically insulative coating on other parts of the instrument to prevent damage to surrounding tissue.
It has been still another object of the invention to speed certain surgical operations through the use of a single cutting instrument having a dual cutting edge blade which allows two distinct cutting operations to be performed on tissue.